摘要 |
A capacitive position sensor comprising a preferably annular sensing path, the sensing path having one or more virtual buttons designated along its length. The sensing path has a plurality of terminals connected to it to subdivide it into a plurality of sections, each terminal providing a sensing channel for a signal indicative of capacitance. The sensing channels provide the signals to a processor, preferably a microcontroller, that is operable to distinguish between a user making a touch to actuate one of the virtual buttons, and a touch to perform a scrolling function. To be determined as a scroll, it is required that there is a succession of detects which span over at least a threshold distance, for example an angular or linear distance. To be determined as a touch, it is required that there is a succession of detects that all lie within one of the pre-assigned virtual button positions.
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